Background: Torsion of greater omentum is rare cause of acute abdomen and it can be primary or secondary. Before the advent of CT, diagnosis was often made intraoperatively by the surgeon however with the widespread and increasing use of computer tomography (CT), omental torsion is being diagnosed preoperatively. This work aims to describe and compare the CT features of primary omental torsion to that of intraoperative findings. Case Report: We present a case of 42 year old man with abdominal pain and constipation who was diagnosed as primary omental torsion by CT scan. Conclusion: Accurate diagnosis of omental torsion is possible by the CT study and it helps in timely surgical intervention to reduced morbidity and mortality.